South Africa Fights Blackouts with Concentrating Solar Power

South Africa is a nation rich in renewable energy resources. It's finally capitalizing on them, thanks in large part to opening up its power market – previously a regulated monopoly – to independent power producers (IPP) and instituting short- and long-term national targets for renewable energy generation capacity.

Experiencing rolling blackouts and committed to developing its renewable energy resources as a path towards sustainable development, South Africa's government on Dec. 11 announced it would triple electricity production from renewable energy sources in order to help alleviate power shortages. In the midst of auctions to procure 3,725 megawatts of energy from biomass, wind, solar and hydropower sources, and an additional 3,200 MWs thereafter, South Africa is now aiming for renewable energy resources to contribute 11.4 gigawatts to the grid as of an as yet unspecified date.

Add at least another 100 megawatts to South Africa's total renewable power generation capacity: It is to come in the form of a concentrating solar power (CSP) plant to be built and operated by Spain's Abengoa, and it will do more than generate clean, renewable power. Making use of molten salt thermal energy storage technology, the Xina Solar One power plant will be able to store five hours worth of energy, doling it out as needs demand even after the sun sets.

South Africa's 100 MW Xina Solar One

As of May 2014, a total of 64 project awards had been made to private-sector groups that must include a local, black-owned enterprise. Private investment in these projects totals $14 billion, with an expected 3,922 megawatts of clean, renewable power to come online. Bid prices have dropped over the course of three successive IPP auction rounds, with average tariffs for solar photovoltaic (PV) projects declining 68 percent and those for wind power projects by 42 percent in nominal terms over a mere 2.5 years.

Partnering with South Africa's Industrial Development Corp. (IDC), the Government Employees Pension Fund represented by Public Investment Corp. (PIC) and Kaxu Community Trust, Abengoa on Dec. 15 signed a 20-year power purchase agreement and secured financing for Xina Solar One.

With an investment totaling approximately $1 billion, Abengoa and partners have secured financing from a group of multilateral and South African banks that includes the African Development Bank, the International Finance Corp., Industrial Development Bank of Southern Africa, RMB, Nedbank and ABSA. The 20-year agreement is with South Africa state power utility Eskom.

Xina Solar One is expected to produce enough power to meet the needs of over 90,000 households while also avoiding over 398,000 metric tons of carbon dioxide emissions per year. In addition to molten salt energy storage, the 100MW Xina One CSP plant will make use of parabolic troughs to concentrate sunlight and generate clean, renewable electric power. Construction is already under way, with Xina Solar One expected to be commissioned in Q3 2017.

Green investment, energy and employment

Building Xina Solar One is expected to create employment for 1,300 people during its peak construction phase. A total of 45 jobs in plant operations and maintenance will also be created, according to Abengoa's press release.

The plant will be located near the town of Pofadder in South Africa's Northern Cape Province, adjacent to the Kaxu Solar One CSP plant. Taken together, the two 100-MW CSP plants will comprise the largest solar energy complex on the African continent, according to Abengoa.

Along with Xina Solar One, Abengoa is in the midst of building Kaxu Solar One and the 50-MW Khi Solar One CSP plant, both of which are at advanced stage of construction. “These three projects contribute to South Africa's goal to introduce up to 17,800 MW of renewable energy by 2030 and reduce its dependence on oil and natural gas,” Abengoa highlights.

24/7 solar

Xina One isn't the first or only solar thermal power plant in which Abengoa is making use of its molten salt thermal energy storage technology to overcome solar energy's intermittent nature. This past May, Abengoa received approval from the Chilean Environmental Service's Evaluation and Review Committee to proceed with construction of the 110-MW Cerro Dominador CSP-thermal energy storage facility in Chile's Atacama Desert region.

Making use of molten salt energy storage technology, Cerro Dominador will be the first solar power facility of any kind “to serve as a baseload power plant,” meaning it is expected to deliver electricity 24 hours a day, seven days a week.

Abengoa was also the first company to build and commission a CSP-molten salt energy storage facility here in the U.S. In October 2013 brought the Solana CSP-thermal energy storage plant online. Solana's molten salt energy storage system can store the equivalent of six hours worth of the plant's 280-MW power output.

*Image credits: 1) Abengoa; 2, 3) South Africa’s Renewable Energy IPP Procurement Program: Success Factors and Lessons